以魔芋葡甘露聚糖与没食子酸为原料,制备没食子酰魔芋葡甘露聚糖。通过单因素试验和正交试验考察缩合剂N,N’-二异丙基碳二亚胺和催化剂4-二甲氨基吡啶的用量、三乙酰没食子酸与魔芋葡甘露聚糖的质量比、反应温度及反应时间对酯化反应的影响。实验结果表明:优选的合成条件为三乙酰没食子酸与N,N’-二异丙基碳二亚胺和4-二甲氨基吡啶的摩尔比为1∶1.5∶0.1,三乙酰没食子酸与魔芋葡甘露聚糖的质量比为2∶1,在100℃下反应4 h,所得酯化产物的平均酯化度为0.593。与魔芋葡甘露聚糖相比,酯化改性产物没食子酰魔芋葡甘露聚糖水溶胶的黏度和稳定性均得到明显改善。

Konjac glucomannan and gallic acid were used as the raw materials to prepare gallic acid konjac glucomannan. The effects of the amounts of N,N'-Diisopropylcarbodiimide and 4-dimethylaminopyridine,mass rate of triacetyl gallic acid and konjac glucomannan,reaction temperature and reaction time on the esterification reaction were investigated through single factor and orthogonal experiments. The results showed that optimal reaction conditions were determined as follows: mole rate of triacetyl gallic acid,N,N'-Diisopropylcarbodiimide and 4-dimethylaminopyridine was 1∶ 1. 5∶ 0. 1; mass rate of triacetyl gallic acid and konjac glucomannan was 2∶ 1; reaction temperature and reaction time were 100 ℃ and 4 h respectively; and the average degree of esterification of triacetyl gallic acid konjac glucomannan was 0. 593. In contrast with konjac glucomannan,both viscosity and stability of the hydrosol of modified konjac glucomannan product were remarkably improved.